This disclosure relates generally to the field of memory devices, and in particular to the ability to keep a file system or partition private when connecting a memory device (i.e., a “memory stick”, a “thumb drive” or similar devices) to a host device.
An external memory device (a memory device) may be connected to a computing device using a wired or wireless connection. A typical wired connection is USB, and a typical wireless connection is Bluetooth. A computing device includes any type of computer that has a processor, microprocessor, or other logic that has the ability to read and write memory and execute instructions. This includes but is not limited to large computers, small PC-style computers and laptops, PDAs, cameras and other video devices, controllers for various uses, and smart cell phones. The computing device may be called the host device, or simply the host.
The host and the memory device communicate using protocol stacks, or their logical and functional equivalent, using executable code or software on each end. The lower level layers of the protocol stack include the hardware and controllers. Using USB as an example, the lower levels will include USB ports/connectors and may include a cable physically between the host and memory device, plus USB controllers and drivers at each end (on the host and memory device). Other types of connections, such as Bluetooth, would have the connections applicable to that connection type (e.g., for Bluetooth a wireless connection is established using, at the lowest layers, Bluetooth controllers and device drivers).
Further up the stack, there will be application programming interfaces (API), one of which will include an application dealing with the management and control of memory devices (mass storage devices). On the host side, there will be an application that requests information about the layout of the memory on the memory device. On the memory device side, there will be code running at the same protocol level that answers the host's request for information. Many memory devices use a logical memory layout that is consistent with the Microsoft® method of laying out memory. This may include a master boot record (MBR) found at the lowest readable memory locations. The MBR contains information on how the memory is configured, including information on up to four partitions. This information is supplied to the host, which uses it to access partitions, file systems, etc., on the memory device.